1. Field
Example embodiments include a composition comprising a mixture of at least one iridium organometallic compound and an electrically conductive polymer, an organic active layer comprising the same, an organic memory device comprising the organic active layer and methods for fabricating the same. Other example embodiments include a composition comprising a mixture of at least one iridium organometallic compound and an electrically conductive polymer, an organic active layer comprising the same, an organic memory device comprising the organic active layer with improved operating characteristics and improved non-volatility, which comprises a first electrode, a second electrode and the organic active layer between the first and second electrodes, and methods for fabricating the same.
2. Description of the Related Art
With the recent developments in digital communication technology, demand for a variety of memory devices has been increasing. For example, portable electronic devices suitable for use in applications including, for example, mobile terminals, smart cards, electronic money, digital cameras, personal digital assistants, digital audio players, multimedia players and others, are required for retaining data in memory even when no power is being applied to the memory device, thereby tending to reduce the memory-related power consumption of the device.
In view of the known limitations of conventional flash memory devices and the processes for fabricating such devices, efforts have continued toward developing next-generation nonvolatile memory devices that overcome at least certain of the limitations associated with conventional silicon-based memory devices and provide one or more advantages over the conventional devices including, for example, increased operating speeds, increased density and/or capacity, reduced power consumption and/or reduced fabrication costs.
Some of these next-generation memories may be generally categorized as, for example, ferroelectric RAMs, magnetic RAMs, phase change RAMs, nanotube memories, holographic memories, organic memories, and/or other groupings that tend to reflect the particular constituent materials used in forming the primary memory cells, and/or the particular configuration of the materials and/or structures within the memory cells utilized in the semiconductor memory devices.
Organic memories, for example, may include an organic active layer formed from an organic material positioned between an upper electrode and a lower electrode to utilize the bistability of resistance values obtained when a voltage may be applied to the devices for storing data. Such organic memories have attracted attention as next-generation memories because they provide the desired non-volatility, which may be an advantage associated with conventional flash memories, while also providing improved processability, reducing fabrication costs and/or improving the degree of integration.
Examples of such an organic memory may utilize a 7,7,8,8-tetracyano-p-quinodimethane (CuTCNQ), which may be an organometallic charge transfer complex compound, as the organic material. Another example includes semiconductor devices comprising an upper electrode, a lower electrode and an intermediate layer between the upper and lower electrodes, wherein the intermediate layer may be formed from a mixture of an ionic salt (e.g., NaCl or CsCl) and a conductive polymer. Other work has suggested organic memory devices comprising organic active layers and a metal nanocluster applied between the organic active layers, but efforts in this area have been hampered by low yields, difficulties in forming suitable metal nanoclusters, and reset voltages of about 0 V, rendering such devices generally unsuitable for widespread use as a nonvolatile organic memory.